Final answer:
The property illustrated in the given identity is the distributive property of multiplication over addition.
Step-by-step explanation:
The property illustrated in the given identity is the distributive property of multiplication over addition. According to this property, when a number is multiplied by a sum, we can distribute the multiplication to each term inside the sum. In the given identity 2(3x + 1) = 6x + 2, we are multiplying the number 2 to each term inside the parentheses, resulting in the expression 6x + 2.